Red dye.



UNITED STATES Patented September 8, 1903,

PATENT OFFICE.

OSCAR NASTVOGEL, OF ELBERFELD, GERMANY, ASSIGNOR TO FARBEN- FABRIKEN OF ELBERFELD (30., OF NEW YORK, N. Y., A CORPORA- TION OF NEW YORK.

RED DYE.

SPECIFICATION forming part of Letters Patent No. 738,227, dated September 8, 1903.

Application filed April 14,1903. Serial No. 152,611. (Specimens) To all whont it ntay concern:

Beit known that I, OSCAR NASTVOGEL,doctor of philosophy, chemist, (assiguor to the FARBENFABRIKEN on ELBERFELD Co. of New York,) residing at Elberfeld, Germany, have invented a new and useful Improvement in Red Dyes; and I hereby declare the following to be a clear and exact description of my invcntion.

My invention relates to the production of new and valuable dyestuffs, being salts of bases having the following general formula:

R meaning the alkyl radical; secondly, splitting off water from the resulting triphenylmethane compound, and, finally, oxidizing the pyrone thus produced to the dyestuff. The new coloring-matters thus obtained being salts of the dye bases with acids are when dry and pulverized from red to reddishbrown powders soluble in water and in alcohol with a red color, the alcoholic solutions showing fluorescence. They dye cotton mordanted with tannin, silk, or wool red shades.

In carrying out my invention practicallyI can proceed as follows, the parts being by weight: A mixture of fourteen parts of o-chlorobenzaldehyde, 37.2 parts of the sulfate of o-methylamido-p-cresol, and five hundred parts of a fifty-per-cent. alcohol is heated on the water-bath until on testing unchanged chlorobenzaldehyde can no longer be found to be contained in the mixture. The scarcelysoluble sulfate of the new triphenylmethane base thus prepared representing colorless needles is filtered off from the cold mixture, washed with water, and dried. It is then dissolved in two hundred and forty parts of an eighty-seven-per-cent. sulfuric acid, and the resulting solution is heated to 100 centigrade until the reaction product will become insoluble in caustic-soda lye. When this point is reached, the pyrone is precipitated by the addition of an access of alkali. For the oxidation the crystalline mass thus obtained is dissolved in one thousand parts of afive-percent. hydrochloric acid, and the solution thus produced is heated to the boil after the addition of one hundred parts of common salt and such a sufficient quantity of ferric ch10- rid until an increase of the dyestuff can, no longer be observed by the further addition of ferric ehlorid.

It may be remarked that the hydrochlorids of the above-defined dyestuff bases can be employed for dyeing; but the other soluble salts or even the free bases themselves may also be used.

When dry and pulverized, the new dyestun having the following formula ori -Inkl l/ l/ 1\'n on,

is a reddish-brown powder soluble in water and in alcohol with a red color having a yel- 10W fluorescence, being soluble in concen-- ing salts of bases having the above-given gen-.

eral formula hereinbefore described, being, when dry and pulverized, from red to brown powders soluble in water and in alcohol with a red color, the alcoholic solutions showing fluorescence; and dyeing cotton mordanted with tannin, wool and silk red shades, substantially as described.

2. The herein-described new dyestufi having, in the shape of the hydrochlorid, the above-given formula, which d yestufi is,when dry and pulverized, a reddish-brown powder soluble in water and in alcohol with a red color showing a yellow fluorescence; being soluble in concentrated sulfuric acid of 66 Baum with a yellow color, a red body being precipitated therefrom by the addition of ice; and dyeing cotton mordanted with tannin, wool and silk red shades, substantially as described.

In testimony whereof I have signed my name in the presence of two subscribing witnesses.

OSCAR NASTVOGEL.

Witnesses:

OTTO Komc, JosEPH LANGE. 

